Thermo Fisher Scientific GRP78 Monoclonal Antibody (C38), eBioscience

Applications and Tested Dilution

Product Specifications

Additional Formats

• Alexa Fluor 488
• Request custom conjugation

Product Specific Information

The monoclonal antibody C38 recognizes human glucose-related protein 78 (GRP78), encoded by the HSPA5 gene. GRP78 functions as an endoplasmic reticulum (ER) chaperone protein and a member of the heat shock protein 70 family. It assists in proper protein folding, prevents aggregation, targets misfolded proteins for degradation, and binds calcium to regulate ER stress and the Unfolded Protein Response (UPR).

Under normal conditions, GRP78 binds to transmembrane sensor proteins PERK, IRE1, and ATF6, keeping them inactive. During ER stress, GRP78 releases these sensors, triggering UPR signaling to the nucleus, slowing protein synthesis, and upregulating ER chaperones.

GRP78 is expressed at basal levels in all adult organs and is essential for embryonic stem cell survival. In cancer cells, GRP78 expression increases due to misfolded protein accumulation, contributing to tumor growth, metastasis, and drug resistance. High GRP78 levels correlate with cancer grade and patient survival in breast, liver, prostate, colon, and gastric cancers.

Applications Reported:
This antibody is suitable for flow cytometry, IHC (formalin-fixed paraffin-embedded sections), microscopy, ELISA, and immunocytochemistry.

Applications Tested:

• ICC: ≤5 µg/mL
• IHC (P): ≤5 µg/mL (using low or high pH antigen retrieval)
  Antibody titration is recommended for optimal performance.

Target Information

GRP78 (78 kDa) belongs to the HSP70 family and resides in the endoplasmic reticulum. It transiently associates with newly synthesized secretory and membrane proteins, and interacts with misfolded proteins for degradation. The KDEL motif at its C-terminus ensures ER retention via the KDEL receptor.

GRP78 is vital for protein folding, degradation of misfolded proteins, and prevention of apoptosis. It interacts with DNAJC10 to facilitate substrate release and maintain cellular homeostasis. GRP78 levels serve as biomarkers of hypoglycemia and have neuroprotective roles against oxidative stress. Reduced GRP78 expression is observed in Alzheimer’s disease and PS1 gene mutations. Induction of GRP78 is linked to antitumor drug resistance.

For Research Use Only. Not for use in diagnostic procedures. Not for resale without express authorization.